U.S. patent application number 10/244658 was filed with the patent office on 2003-06-19 for seat heater and a manufacturing method of seat heater.
This patent application is currently assigned to Kurabe Industrial Co., Ltd.. Invention is credited to Hase, Yasuhiro, Ishiyama, Tomokazu, Koide, Osamu, Saito, Masatsugu.
Application Number | 20030111454 10/244658 |
Document ID | / |
Family ID | 19110449 |
Filed Date | 2003-06-19 |
United States Patent
Application |
20030111454 |
Kind Code |
A1 |
Ishiyama, Tomokazu ; et
al. |
June 19, 2003 |
Seat heater and a manufacturing method of seat heater
Abstract
To provide a seat heater and the manufacturing method thereof,
having the stable adherent strength between the heating wire and
the base cloth for a long time, with a good seat feeling, at a
lower cost. The seat heater is comprising, a base cloth mixed with
heat bonding filament, and a heating wire having a heat bonding
layer and being placed in a predetermined pattern shape, in order
to adhere to and be fixed on the base cloth by heat bonding under
heat and pressure. Thus the stable adherent strength between the
heating wire and the base cloth may be maintained for a long time,
with a good seat feeling, at a lower cost.
Inventors: |
Ishiyama, Tomokazu;
(Hamamatsu-shi, JP) ; Saito, Masatsugu;
(Hamamatsu-shi, JP) ; Hase, Yasuhiro;
(Hamamatsu-shi, JP) ; Koide, Osamu;
(Hamamatsu-shi, JP) |
Correspondence
Address: |
McGinn & Gibb, PLLC
8321 Old Courthouse Road, Suite 200
Vienna
VA
22182-3817
US
|
Assignee: |
Kurabe Industrial Co., Ltd.
Hamamatsu-shi
JP
|
Family ID: |
19110449 |
Appl. No.: |
10/244658 |
Filed: |
September 17, 2002 |
Current U.S.
Class: |
219/217 ;
219/529 |
Current CPC
Class: |
B60N 2/5635 20130101;
B60N 2/5628 20130101; B60N 2/5685 20130101; B60N 2/565
20130101 |
Class at
Publication: |
219/217 ;
219/529 |
International
Class: |
H05B 003/34 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 20, 2001 |
JP |
2001-287680 |
Claims
What is claimed is:
1. A seat heater comprising: a base cloth being mixed with heat
bonding filament; and a heating wire having a heat bonding layer
and being placed in a predetermined pattern shape on said base
cloth, whereby said heating wire may adhere to and be fixed on said
base cloth, by means of heat bonding under application of heat and
pressure.
2. The seat heater as claimed in claim 1, wherein: said heat
bonding layer of said heating wire being provided at the top
surface layer of said heating wire.
3. The seat heater as claimed in claim 2, wherein: said heating
wire adhering to and being fixed on said base cloth, in a form that
said base cloth being dented by said heating wire.
4. The seat heater as claimed in claim 1, wherein: said heat
bonding filament of said base cloth being filament, having a
core-sheath combination structure, in which, heat bonding resin
serves as the sheath.
5. The seat heater as claimed in claim 4, wherein: said filament
having said core-sheath combination structure, in which said heat
bonding resin serves as the sheath, shall be filament selected
among the group of, filament having said core-sheath combination
structure in which low-melting point polypropylene serves as the
sheath, and filament having said core-sheath combination structure
in which polyethylene serves as the sheath, and filament having
said core-sheath combination structure in which low-melting point
polyester serves as the sheath.
6. The seat heater as claimed in claim 1, further comprising:
detached part, at which said heating wire may be detached from said
base cloth without being pulled together with said base cloth, at
portion where pulling force being applied to said base cloth toward
a seat serving as an object of installation.
7. The seat heater as claimed in claim 6, further comprising:
non-bonding portion serving as said detached part, at which said
heating wire not adhering to and being not fixed on said base
cloth.
8. The seat heater as claimed in claim 1, wherein: said base cloth
being mixed with said heat bonding filament, at a mixing rate of
said heat bonding filament between 5% and 15%.
9. The seat heater as claimed in claim 1, wherein: said base cloth
adhering to not less than 30% of an outer periphery of said heating
wire.
10. The seat heater as claimed in claim 1, wherein: said heat
bonding layer of said heating wire being in color.
11. The seat heater as claimed in any of claim 1 through claim 10,
wherein: said seat heater being incorporated in a vehicle seat.
12. The seat heater as claimed in claim 11, wherein: said vehicle
seat being equipped with an air conditioner.
13. A manufacturing method of seat heater, comprising: a step of
placing and forming a heating wire having a heat bonding layer, in
a predetermined pattern shape on a press aid; a step of placing a
base cloth, mixed with heat bonding filament, facing to said
heating wire formed and placed in said predetermined pattern shape;
and a step of moving a pressing plate positioned to be facing to
said press aid, so that said pressing plate may relatively become
close to said press aid, whereby said heating wire adhering to and
being fixed on said base cloth under heat and pressure applied to
each other.
14. The manufacturing method of seat heater as claimed in claim 13,
wherein: predetermined part of said press aid or said pressing
plate being provided with hollow part, whereby detached part may be
provided, at which said heating wire may be detached from said base
cloth without being pulled together with said base cloth.
15. The seat heater as claimed in claim 14, wherein: A state of
said detached part may be arbitrarily determined by adjusting the
depth of said hollow part.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a seat heater which may be
used for e.g. heating of a vehicle seat, and a manufacturing method
of the seat heater. More particularly, the present invention
relates to a seat heater in which, a heating wire is provided on a
base cloth, thereby the sufficient and stable adherent strength
between the heating wire and the base cloth may be maintained for a
long period of time, and in which a good seat feeling may be
accomplished at a lower cost.
[0003] 2. Description of the Related Art
[0004] There have been several conventional seat heaters, for
example, a heater in which a winding (zig-zag) form of heating wire
is placed on a sewable supporting body such as a cloth, so that the
heating wire may be sewn and secured to the cloth by upper thread
and lower thread (e.g. see a patent document 1), or a heater in
which a winding (zig-zag) form of heating wire is placed on a
supporting body such as a cloth, and is then caught and fixed
between a pair of cloth sheets of which surfaces are coated with
adhesive agents (e.g. see a patent document 2).
[0005] These seat heaters are actually used, for example by being
inserted into a position between a seat pad and a surface cover of
a vehicle seat.
[0006] Patent Document 1:
[0007] Official Gazette of Japanese Patent No. 2621437 (columns
4-6, FIG. 3); and
[0008] Patent Document 2:
[0009] Official Gazette of Japanese Examined Patent Publication No.
Sho 63-19068 (column 3, FIG. 5).
[0010] In addition, although not prior arts directly relating to
the seat heater, there are three cases which might have any
relation as follows:
[0011] Patent Document 3:
[0012] Official Gazette of Japanese Examined Utility Model
Publication No. Hei 6-25916;
[0013] Patent Document 4:
[0014] Official Gazette of Japanese Unexamined Patent Publication
No. Hei 6-68964; and
[0015] Patent Document 5:
[0016] Official Gazette of Japanese Unexamined Patent Publication
No. Hei 6-119967;
[0017] However, the above prior arts have the following
disadvantages.
[0018] First, according to the structure in which the heating wire
is sewn and fixed on the supporting body (i.e. the prior art as
shown in the patent document 1), when a passenger sits on and
leaves the seat, the application and the release of the load of the
passenger shall repeatedly occur, thereby the thread might be
loosened or cut, which would further result in a deviation of the
heating wire inside the seat. When the heating wire is deviated
from the regular position, there is a possibility that the seat may
not be heated uniformly. This is very dangerous, since the deviated
heating of the seat might cause the concentrated overheating of any
part of the seat.
[0019] Thus, there have been several suggestions as the
countermeasure therefor, for example to reduce the sewn pitch
during fixing of the heating wire, or to fix the heating wire more
tightly by increasing the sewing strength. However, in these cases,
the supporting body must be made of any material having a
sufficient thickness, and must also at least satisfy a required
hardness.
[0020] However, when the above discussed supporting body is
selected, there would arise another problem that the touch of the
seat heater might become hardened, and thereby the seat feeling
might become poor.
[0021] Further, as the fixing of the seat heater by sewing is very
laborious, and the productivity is not good. Accordingly, there is
another problem that the production cost would become higher.
[0022] On the other hand, according to the structure in which the
heating wire is inserted and fixed in a position between the pair
of cloth sheets with the adhesive agents thereon (i.e. the prior
art as shown in the patent document 2), as the two supporting
bodies must be used, and there exists the layer of the adhesive
agent between these sheets, the touch might also become hardened,
and the seat feeling might also become poor.
[0023] Further, this type of seat heater requires many component
parts, and since the cloth sheet, of which surface being coated
with the adhesive, is very expensive, the production cost would
increase considerably.
SUMMARY OF THE INVENTION
[0024] It is an object of the present invention to provide a seat
heater in which, the stable adherent strength between the heating
wire and the base cloth may be maintained for a long period of
time, and in which a good seat feeling may be accomplished at a
lower cost. Further, it is another object of the present invention
to provide a method to manufacture such seat heater.
[0025] To achieve the object mentioned above, according to claim 1
of the present invention, there is provided a seat heater,
comprising, a base cloth being mixed with heat bonding filament;
and a heating wire having a heat bonding layer and being placed in
a predetermined pattern shape on the base cloth, whereby the
heating wire may adhere to and be fixed on the base cloth, by means
of heat bonding under application of heat and pressure.
[0026] According to claim 2 of the present invention, there is
provided the seat heater of claim 1, wherein the heat bonding layer
of the heating wire is provided at the top surface layer of the
heating wire.
[0027] According to claim 3 of the present invention, there is
provided the seat heater of claim 2, wherein, the heating wire is
adhering to and fixed on the base cloth, in a form that the base
cloth is dented by the heating wire.
[0028] According to claim 4 of the present invention, there is
provided the seat heater as claimed in claim 1, wherein, the heat
bonding filament of the base cloth is filament, having a
core-sheath combination structure, in which, heat bonding resin
serves as the sheath.
[0029] According to claim 5 of the present invention, there is
provided the seat heater of claim 4, wherein, the filament having
the core-sheath combination structure, in which the heat bonding
resin serves as the sheath, shall be filament having the
core-sheath combination structure in which low-melting point
polypropylene serves as the sheath, or filament having the
core-sheath combination structure in which polyethylene serves as
the sheath, or filament having the core-sheath combination
structure in which low-melting point polyester serves as the
sheath.
[0030] According to claim 6 of the present invention, there is
provided the seat heater of claim 1, further comprising detached
part, at which the heating wire may be detached from the base cloth
without being pulled together with the base cloth, at portion where
pulling force is applied to the base cloth toward a seat serving as
an object of installation.
[0031] According to claim 7 of the present invention, there is
provided the seat heater of claim 6, further comprising non-bonding
portion serving as the detached part, at which the heating wire
does not adhere to and is not fixed on the base cloth.
[0032] According to claim 8 of the present invention, there is
provided the seat heater of claim 1, wherein the base cloth is
mixed with the heat bonding filament, at a mixing rate of the heat
bonding filament between 5% and 15%.
[0033] According to claim 9 of the present invention, there is
provided the seat heater of claim 1, wherein the base cloth is
adhering to not less than 30% of an outer periphery of the heating
wire.
[0034] According to claim 10 of the present invention, there is
provided the seat heater of claim 1, wherein the heat bonding layer
of the heating wire is in color.
[0035] According to claim 11 of the present invention, there is
provided the seat heater of any of claim 1 through claim 10,
wherein the seat heater is incorporated in a vehicle seat.
[0036] According to claim 12 of the present invention, there is
provided the seat heater of claim 11, wherein the vehicle seat is
equipped with an air conditioner.
[0037] According to claim 13 of the present invention, there is
provided a manufacturing method of seat heater, comprising, a step
of placing and forming a heating wire having a heat bonding layer,
in a predetermined pattern shape on a press aid; a step of placing
abase cloth, mixed with heat bonding filament, facing to the
heating wire formed and placed in the predetermined pattern shape;
and a step of moving a pressing plate positioned to be facing to
the press aid, so that the pressing plate may relatively become
close to the press aid, whereby the heating wire adheres to and is
fixed on the base cloth under heat and pressure applied to each
other.
[0038] According to claim 14 of the present invention, there is
provided the manufacturing method of seat heater of claim 13,
wherein, predetermined part of the press aid or the pressing plate
is provided with hollow part, whereby detached part may be
provided, at which the heating wire may be detached from the base
cloth without being pulled together with the base cloth.
[0039] And according to claim 15 of the present invention, there is
provided the seat heater of claim 14, wherein a state of the
detached part may be arbitrarily determined by adjusting the depth
of the hollow part.
[0040] Therefore, according to the seat heater of the present
invention, the seat heater is provided with the base cloth being
mixed with the heat bonding filament, and the heating wire having
the heat bonding layer and being placed in a predetermined pattern
shape on the base cloth, whereby the heating wire may adhere to and
be fixed on the base cloth, by means of heat bonding under
application of heat and pressure. Consequently, the seat heater may
have the stable adherent strength between the heating wire and the
base cloth for a long time, with a good seat feeling, at a lower
cost. This is a novel structure of the seat heater, and this also
express the inherent function and effect of the present
invention.
[0041] Preferably, the seat heater may be provided at the top
surface layer of the heating wire. In this case, the heating wire
may be effectively melted, and hence, may adhere to and be fixed on
the base material.
[0042] Preferably, the seat heater may adhere to and be fixed on
the base cloth, in a form that the base cloth is dented by the
heating wire. Consequently, the wide adherent area may be secured,
and thus the strong adherent state may be obtained. Further, since
the protrusive amount of the heating wire may be minimized, thereby
the good seat feeling may be obtained.
[0043] Preferably, the heat bonding filament of the base cloth is
may be any filament, having the core-sheath combination structure,
in which the heat bonding resin serves as the sheath. For example,
it is possible to use the filament having the core-sheath
combination structure in which the low-melting point polypropylene
serves as the sheath, or the filament having the core-sheath
combination structure in which polyethylene serves as the sheath,
or the filament having the core-sheath combination structure in
which the low-melting point polyester serves as the sheath.
[0044] The material of the filament is of course not limited to the
above filament materials.
[0045] Further, the seat heater may be provided with the detached
part, at which the heating wire may be detached from the base cloth
without being pulled together with the base cloth, at the portion
where the pulling force is applied to the base cloth toward a seat
serving as an object of installation. At such part, the heating
wire might be pulled together with the base cloth, which would
cause the heating wire being cut. Therefore, when the detached part
is provided at such part, even when the base cloth is pulled, no
harmful effect will be given to the heating wire, and eventually
there is no risk of the heating wire being cut.
[0046] Preferably, the non-bonding portion serving as the detached
part, at which the heating wire does not adhere to and is not fixed
on the base cloth, may be provided. Further, it will be possible to
provide, for example, the non-bonding portions and the bonding
portions one after another, so that they may serve as the detached
part, or the adhering and fixed part at which adherent strength is
small, so that it may serve as the detached part.
[0047] Preferably, the base cloth may be mixed with the heat
bonding filament, at a mixing rate of the heat bonding filament
between 5% and 15%. When the mixing rate of the heat bonding
filament is less than 5%, the sufficient adherent strength between
the heating wire and the base cloth may not be obtained. On the
other hand, when the mixing rate of the heat bonding filament is
more than 15%, the base cloth may be hardened, which would result
in the poor touch feeling of the seat.
[0048] However, if it is expected to obtain a certain degree of
this effect, the present invention is not limited to the above
value.
[0049] Preferably, the base cloth may adhere to not less than 30%
of the outer periphery of the heating wire, for the purpose of
obtaining the good adherent strength.
[0050] However, if it is also expected to obtain a certain degree
of this effect, the present invention is not limited to the above
value.
[0051] Preferably, the heat bonding layer of the heating wire may
be in color, so that the bonding state (adherent state) between the
heating wire and the base cloth may be confirmed easily by the
eyes. That is, as for the seat heater in which the heating wire and
the base cloth have been melted and bonding to each other, when an
inspector sees the seat heater from the reverse side (the side on
which the heating wire is not placed), the inspector may see the
transparent color of the heat bonding layer of the heating wire.
And on the other hand, if there is any trouble in regard to the
heat bonding state between the heating wire and the base cloth, the
inspector cannot see the transparent color of the heat bonding
layer of the heating wire. This function is very useful from the
viewpoint of the quality control of the products. The present
invention may also express such secondary effect.
[0052] The seat heater according to the present invention may be
used for various purposes, and for example, the seat heater may be
incorporated in a vehicle seat.
[0053] For example, the vehicle seat may be equipped with the air
conditioner. In this case, since the seat heater according to the
present invention has the simple structure that the heating wire
adheres to and is fixed on a single sheet of the base cloth, the
seat heater has a good ventilation performance, and there is no
possibility that the seat heater would cause any bad effect to the
air supply by the air conditioner.
[0054] According to the manufacturing method of seat heater of the
present invention, first, the heating wire having the heat bonding
layer is placed and formed, in a predetermined pattern shape on the
press aid. Thereafter, the base cloth, mixed with the heat bonding
filament, is placed, facing to the heating wire formed and placed
in the predetermined pattern shape. Thereafter, the pressing plate,
positioned to be facing to the press aid, is moved, so that the
pressing plate may relatively become close to the press aid,
whereby the heating wire adheres to and is fixed on the base cloth
under heat and pressure applied to each other. Thus the desired
seat heater may be effectively produced.
[0055] Preferably, predetermined part of the press aid or the
pressing plate may be provided with the hollow part, whereby the
detached part may be provided, at which the heating wire may be
detached from the base cloth without being pulled together with the
base cloth. Thus, it is possible to obtain the seat heater having
the detached part at the arbitrary position.
[0056] Preferably, the state of the detached part may be
arbitrarily determined by adjusting the depth of the hollow part.
In regard to the adjusting means for the hollow part, for example,
it is possible to change and set the depth of the hollow part
depending on each case, or it is also possible to adjust the depth
by intervening elastic materials, etc., having an appropriate
thickness, in the hollow part. Accordingly, it is possible to
provide the various form of the detached part, for example, in
which the non-bonding portions and the bonding portions are
provided one after another, so that they may serve as the detached
part, or which adheres to and is fixed on the base cloth by a small
adherent strength, in order to serve as the detached part.
[0057] As discussed above, according to the seat heater of the
present invention, the base cloth being mixed with the heat bonding
filament, adheres to and is fixed on the heating wire, having the
heat bonding layer and being placed in a predetermined pattern
shape on the base cloth, by means of heat bonding under application
of heat and pressure. Consequently, the good touch feeling of the
seat is not deteriorated, and the sufficient adherent strength
between the heating wire and the base cloth may be maintained for a
long period of time.
[0058] Further, the complicated sewing procedure in the prior art
is no longer required.
[0059] Further, the number of essential parts may be remarkably
reduced, thereby the production cost will be also remarkably
reduced. Thus, the seat heater may be provided at a lower cost.
[0060] Where the seat heater is provided at the top surface layer
of the heating wire, the heating wire may be effectively melted,
and hence, may adhere to and be fixed on the base material.
[0061] Where the seat heater adheres to and is fixed on the base
cloth in a form that the base cloth is dented by the heating wire,
the wide adherent area may be secured, and thus the strong adherent
state may be obtained. Further, since the protrusive amount of the
heating wire may be minimized, the good seat feeling may be
obtained.
[0062] Where the seat heater is provided with the detached part,
even when the pulling force is applied to the base cloth toward a
seat serving as an object of installation, and thereby the base
cloth is pulled, no harmful effect will be given to the heating
wire, and there is no risk of the heating wire being cut.
[0063] Where the base cloth is mixed with the heat bonding
filament, at a mixing rate of the heat bonding filament between 5%
and 15%, the sufficient adherent strength may be obtained between
the heating wire and the base cloth, and it is also possible to
prevent the base cloth from being hardened, which would cause the
poor touch feeling of the seat.
[0064] Where the base cloth adheres to not less than 30% of the
outer periphery of the heating wire, the good adherent strength may
be obtained.
[0065] Where the heat bonding layer of the heating wire is in
color, it is possible to also obtain the secondary effect, that the
bonding state (adherent state) between the heating wire and the
base cloth may be confirmed easily by the eyes.
[0066] Where the seat heater is incorporated in a vehicle seat
equipped with the air conditioner, since the seat heater of the
present invention has the simple structure that the heating wire
adheres to and is fixed on a single sheet of the base cloth, the
seat heater has a good ventilation performance, and there is no
possibility that the seat heater would cause any bad effect to the
cold/hot air supply by the air conditioner.
[0067] Further, according to the manufacturing method of seat
heater of the present invention, it is possible to easily produce
the seat heater having the desired structure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0068] The invention will be described below in detail with
reference to the accompanying drawings, in which:
[0069] FIG. 1 is a side view showing a structure of a heating wire
in which several structural elements being partially cut out
therefrom, according to a first embodiment of the present
invention;
[0070] FIG. 2 is side view showing a structure of a hot pressing
type of heater manufacturing apparatus according to the first
embodiment of the present invention;
[0071] FIG. 3 is a partial perspective view showing a state that
the heating wire is placed in a predetermined pattern form
according to the first embodiment of the present invention;
[0072] FIG. 4 is a plan view of showing a structure of the seat
heater according to the first embodiment of the present
invention;
[0073] FIG. 5 is a perspective view showing a state that the seat
heater is embedded in a vehicle seat, in which several structural
elements of the vehicle seat being partially cut out therefrom,
according to the first embodiment of the present invention;
[0074] FIG. 6 is an enlarged sectional view showing a joint part at
which the heating wire adheres to and is fixed on a base cloth,
according to the first embodiment of the present invention;
[0075] FIG. 7 is a side view showing a structure of a heating wire
in which several structural elements being partially cut out
therefrom, according to a second embodiment of the present
invention;
[0076] FIG. 8 is a side view showing a structure of a heating wire
in which several structural elements being partially cut out
therefrom, according to a third embodiment of the present
invention;
[0077] FIG. 9 is a side view showing a structure of a heating wire
in which several structural elements being partially cut out
therefrom, according to a fourth embodiment of the present
invention;
[0078] FIG. 10 is side view showing a structure of a hot pressing
type of heater manufacturing apparatus according to a fifth
embodiment of the present invention; and
[0079] FIG. 11 is a sectional view of a vehicle seat according to a
sixth embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
First Embodiment
[0080] A first embodiment of the present invention will now be
described with reference to FIGS. 1 through 6. The first embodiment
will show an example presuming that the present invention is
applied to a seat heater for vehicles.
[0081] The structure of a heating wire 1 according to the first
embodiment will now be made, with reference to FIG. 1. There is a
heater core 3 made of a bundle of aromatic polyamide fibers of
which outer diameter is about 0.2 mm, and a heating body 5 twists
in the spiral shape around the outer periphery of the heater core
3, at a pitch about 0.7 mm. The heating body 5 comprises six
paralleled string heaters, of which respective outer diameter is
0.08 mm, made of tin plated had copper-tin alloy (TH-SNCC-3). The
outer periphery of the above discussed heating body 5 is coated by
an extruded insulating layer 7, having the thickness of about 0.15
mm, and made of the copolymer of tetrafluoroethylene and
hexafluoropropylene (FEP). Further, the outer periphery of the
insulating layer 7 is coated by an extruded heat bonding layer 9,
having the thickness of 0.2 mm, and made of polyethylene (PE). This
is the structure of the heating wire 1, of which outer diameter as
the finished product is 1.1 mm.
[0082] As above discussed, according to the present embodiment, the
heat bonding layer 9 is provided on the outer periphery of the
insulation layer 7, as the separate layer. However, it is also
possible, for example, to provide a single layer composed of the
mixture of the two layers.
[0083] Further, although the above heater core 3 has the effective
strength when considering the bending strength (flexibility) or the
tensile strength, it is also possible to use, instead of the heater
core 3, a heating body made of a plurality of paralleled string
heaters, or a stranded string heaters.
[0084] The structure of a base cloth 11 (shown in FIGS. 2 through
4), serving as the base material for the adhesion and fixing of the
heating wire 1 as discussed above, will now be described. The base
cloth 11 according to the present embodiment is made the mixture of
non-woven fabric (of which weight per unit area is 100 g/m.sup.2,
and the thickness is 0.6 mm), with a predetermined percentage (3%,
5%, 10%, 15% or 30%) of core-sheath combination filament of which
sheath is made of low-melting point polyester serving as a heat
bonding filament (hereinafter "low-melting point polyester
filament").
[0085] The mixture having 3% of the low-melting point polyester
filament shall be used in "a first embodiment". Similarly, the
mixture having 5% of the low-melting point polyester shall be used
in "a second embodiment", that having 10% of the low-melting point
polyester shall be "a third embodiment", that having 15% of the
low-melting point polyester shall be "a fourth embodiment", and
that having 30% of the low-melting point polyester shall be "a
fifth embodiment".
[0086] As discussed above, although the embodiments of the present
invention uses the core-sheath combination filament of which sheath
is made of low-melting point polyester as the heat bonding
filament, it is also possible to use, for example, core-sheath
combination filament of which sheath is made of low-melting point
polypropylene, or core-sheath combination filament of which sheath
is made of polyethylene, etc.
[0087] Although the size and the thickness of the base cloth 11 may
vary almost freely according to the purpose of use, preferably, the
thickness (measured in the dry state) may be e.g. between 0.6 mm
-1.4 mm. If such thickness of the base cloth 11 is selected, when
the heating wire 1 adheres to and is fixed on the base cloth 11 by
heat and pressure, not less than 30% of the outer periphery of the
heating wire 1, or preferably not less than 50% thereof, may
effectively adhere to the base cloth 11, thereby the two materials
may strongly adhere to each other. This state will be explained in
detail afterwards.
[0088] Now the structure of adhesion and fixing of the heating wire
1 on the base cloth 11 as discussed above, by placing the heating
wire 1 in a predetermined pattern form on the base cloth 11, will
now be explained. FIG. 2 illustrates the structure of a hot-press
type heater manufacturing apparatus 13, whereby the heating wire 1
may adhere to and be fixed on the base cloth 11. There is a hot
pressing aid 15, on which upper surface is provided with a
plurality of hooking devices 17. As illustrated in FIG. 3, each of
the hooking devices 17 is provided with a pin 19, upwardly inserted
in a hole 21 from the bottom of the hot pressing aid 15. The hole
21 has been drilled in the hot pressing aid 15. There is a hooking
member 23 at the upper part of the pin 19, so that the hooking
member 23 may move in the axial direction of the pin 19. There is a
coil spring 25, which always applies the force upwardly to the
hooking member 23. Further, as illustrated by an imaginary line of
FIG. 3, the heating wire 1 is hooked on each of the hooking members
23 of the hooking devices 17, so that the heating wire 1 is placed
in a predetermined pattern form.
[0089] Now referring back to FIG. 2, there is a pressing hot plate
27 having an elevation mechanism, above the plurality of the
hooking devices 17. First, the heating wire 1 is hooked on the
plurality of the hooking members 23 of the hooking devices 17, so
that the heating wire 1 may be placed in the predetermined pattern
form, and the base cloth 11 is laid on the top of these hooking
members 23. In that state, the pressing hot plate 27 goes down, so
that the heat and pressure, for example, at the temperature of
230.degree. C., for 5 seconds, may be applied to the heating wire 1
and the base cloth 11. Thus, a heat bonding layer 9 on the side of
the heating wire 1, and the heat bonding filament on the side of
the base cloth 11, that is the low-melting point polyester
filament, maybe melted and connected to each other, thereby the
heating wire 1 may adhere to and be fixed on the base cloth 11.
[0090] When the pressing hot plate 27 goes down in order to apply
the pressure and heat, the plurality of the hooking members 23 of
the hooking devices 17 will go down, against the upward force of
the coil springs 25 applied to the hooking members 23.
[0091] Consequently, it is possible to obtain a seat heater 31 for
a vehicle, as illustrated in FIG. 4.
[0092] The both ends of the heating wire 1 of the seat heater 31 as
discussed above, are electrically connected to a cable 33, and the
end of the cable 33 has a connector 35, by which the seat heater 31
may be electrically connected to an unillustrated electric system
of the vehicle.
[0093] The seat heater 31 having the structure as discussed above
is incorporated in a vehicle seat 41, as illustrated in FIG. 5.
According to FIG. 5, the seat heater 31 is inserted in a position
between a surface cover 43 and a seat pad 45.
[0094] FIG. 6 is an enlarged view showing the state that the
heating wire 1 adheres to and is fixed on the base cloth 11. As
illustrated in FIG. 6, when the heating wire 1 adheres to and is
fixed on the base cloth 11, not less than 30%, and preferably not
less than 50% of the outer periphery of the heating wire adhere to
the base cloth 11 with a sufficient strength. In this connection,
"not less than 30%" or "not less than 50%" does not mean the value,
obtained by the total area of adhering part, in which the heat
bonding filament as the essential element of the base cloth 11,
i.e. the low-melting point polyester adheres to the heat bonding
layer 9 on the outer periphery of the heating wire 1, being divided
by the total surface area of the heating wire. Instead, as
illustrated in FIG. 6, this means the value of the apparent
adhering area as viewed in the sectional direction of the seat
heater 31 when the heating wire 1 adheres to the base cloth 11
(i.e. the percentage obtained in the manner that the distance
between a point "a" and a point "b" being divided by the
circumferential length of the outer periphery of the heating wire
1). Thus, the heating wire 1 adheres to and is fixed on the base
cloth 11 more strongly. Further, at that time, the heating wire 1
is placed in a form that the base cloth 11 is dented by the heating
wire 1. Therefore, for example, when the heating wire 1 is provided
in the vehicle seat 41, the heating wire 1 will not protrude from
the surface cover 43 of the vehicle seat 41, and the passenger may
not feel the existence of any foreign articles.
[0095] The thus obtained five types of seat heater 31 (the example
1 through the example 5) were used as the samples, in order to
assess the characteristics in regard to the touch (seat feeling)
and the adherent strength thereof. The result will be shown in the
Table 1 below:
1 TABLE 1 Exp. 1 Exp. 2 Exp. 3 Exp. 4 Exp. 5 Low-melting point
polyester 3 5 10 15 30 filament mixture rate (%) Non-woven fabric
100 100 100 100 100 unit volume (g/m.sup.2) Non-woven fabric
thickness 0.6 0.6 0.6 0.6 0.6 (mm) Feeling of existing 0 0 0 0 80
any foreign article (%) Adherent strength (N/piece) 3 9.8 10.7 11.4
12.0 State of destruction 3/5 5/5 5/5 5/5 5/5 partially material
material material material exfoliated destroyed destroyed destroyed
destroyed
[0096] First, as for the touch (seat feeling) of each example, the
seat heater 31 was inserted in a position between the seat pad 45
and the surface cover 43 of the vehicle seat 41, and ten people
actually sat on the respective vehicle seats 41. The ten people
were then questioned if there was any feeling of a foreign article,
as compared with the other same type of vehicle seats 41 in which
the seat heaters 31 were not provided respectively.
[0097] According to the test result, there was no one that felt the
existence of the foreign article as for the vehicle seats 41,
respectively provided with the seat heater 31 having within 15% of
the low-melting point polyester filament mixture (i.e. the example
1 through the example 4). However, as for the vehicle seat 41
provided with the seat heater 31 of which mixture rate of the
low-melting point polyester filament was exceeding 15% (i.e. the
example 5), eight people felt the existence of the foreign
article.
[0098] As for the adherent strength, the adherent strength of each
sample was measured based on the T-type exfoliation test method
prescribed under Japan Industrial Standard (JIS) K 6854, and the
maximum value when being pulled at the speed of 500 mm/min was used
as the detected value. In addition, the state of destruction was
also recorded. The result is as per illustrated in the above Table
1.
[0099] As a result, the sufficient adherent strength was obtained
for a long period of time, as for the seat heaters 31 of which
mixture rates of the low-melting point polyester filament are not
less than 5% (the example 2 through the example 5). However, as for
the vehicle seat 41 provided with the seat heater 31 of which
mixture rate of the low-melting point polyester filament was less
than 5% (i.e. the example 1), the heating wire 1 was exfoliated
from the base cloth 11.
[0100] According to the test result as discussed above, it was
proven that the seat heater 31 having a good touch feeling as well
as the sufficient adherent strength could be obtained when the
mixture rate of the low-melting point polyester filament serving as
the structural element of the base cloth 11 was between 5% and
15%.
[0101] There was a further test executed according to the present
embodiment, in which, three types of seat heater 31 were prepared
by varying the unit volume and the thickness of the non-woven
fabric, and by setting the fixed mixture rate of the low-melting
point polyester filament as 5%, respectively (the example 6 through
the example 8; the example 6 was the same sample as the example 2),
in order to obtain the adherent strength data. At the same time,
the adherent rate between the outer periphery of the heating wire 1
and the non-woven fabric was measured. The structure of examples,
other than the non-woven fabric, was the same as that of the
example 1 through example 5 discussed above. The result will be
shown in the Table 2 below:
2 TABLE 2 Exp. 6 Exp. 7 Exp. 8 Low-melting point polyester 5 5 5
filament mixture rate (%) Non-woven fabric unit volume (g/m.sup.2)
100 120 150 Non-woven fabric thickness 0.6 0.9 1.4 (mm) Feeling of
existing 0 0 0 any foreign article (%) Adherent strength (N/piece)
9.8 11.0 13.2 State of destruction 5/5 5/5 5/5 material material
material destroyed destroyed destroyed Adherent rate of the outer
30 50 70 periphery of heater (%)
[0102] As a result, each example expressed the sufficient adherent
strength, and among others, the best adherent strength was obtained
in the case of the example 8, i.e. the unit volume of the non-woven
fabric was 150 g/m.sup.2, and the thickness thereof was 1.4 mm.
According to the example 8, it was also proven that 70% of the
outer periphery of the heating wire 1 adhered to the non-woven
fabric. Although the example 6 showed the lowest adherent strength
(9.8 N), this value would still be in the scope of the sufficient
strength for practical use. The example 6 also showed that 30% of
the outer periphery of the heating wire 1 adhered to the non-woven
fabric. Consequently, it was proven that, if at least 30% of the
outer periphery of the heating wire 1 adhered to the base cloth 1,
the seat heater 31 according to the present invention could obtain
the sufficient adherent strength for practical use.
Second Embodiment
[0103] A second embodiment of the present invention will now be
described with reference to FIG. 7. According to the first
embodiment as discussed above, as an example showing the
fundamental structure of the heating wire, it is described that the
heating body is provided, in which a plurality of paralleled string
heaters wound around the outer periphery of the heater core.
However, the present invention is of course not limited to this
first embodiment.
[0104] For example, according to the second embodiment, it is also
possible to apply the present invention to a so-called "high
tensile strength type" of heating wire 51 as illustrated in FIG. 7.
The detailed explanation will be made below.
[0105] The structure of the heating wire 51 according to the second
embodiment will now be made. There is a core 53 made of a bundle of
aromatic polyamide fibers, and a heating body 55 twists in the
spiral shape around the outer periphery of the heater core 53. The
heating body 55 is in the shape of a stranded string heaters made
of copper string or copper-nickel alloy string. The outer periphery
of the above discussed heating body 55 is coated by an extruded
insulating layer 57, having the thickness of about 0.15 mm, and
made of the copolymer of tetrafluoroethylene and
hexafluoropropylene (FEP). Further, the outer periphery of the
insulating layer 57 is coated by an extruded heat bonding layer 59,
having the thickness of 0.2 mm, and made of polyethylene (PE). This
is the structure of the heating wire 51, of which outer diameter as
the finished product is 1.1 mm.
[0106] Accordingly, it is also possible to apply the present
invention to this "high tensile strength type" of heating wire 51
as discussed above, in the same manner as that of the first
embodiment, thereby the almost same effect as that of the first
embodiment may be obtained.
Third Embodiment
[0107] A third embodiment of the present invention will now be
described with reference to FIG. 8. FIG. 8 illustrates the
structure of a so-called "single-wire type" of heating wire 61, and
it is also possible to apply the present invention to this type
which means of the heating wire 61, likewise the case of the first
embodiment and the second embodiment.
[0108] The structure of the heating wire 61 according to the third
embodiment will now be made. There is a heater core 63 made of a
glass fiber or a polyester fiber, and a heating body 65 twists in
the spiral shape around the outer periphery of the heater core 63.
The heating body 65 comprises a string heater.
[0109] It is also possible that the heating body 65 may comprise a
plurality of the string heaters.
[0110] The outer periphery of the above discussed heating body 65
is coated by an extruded fuse layer 67, made of resin categorized
as polyamide such as nylon-11 or nylon-12. Further, there is a
nickel wire 69 serving as a heat detecting line and as a signal
line, twisting in the spiral shape around the outer periphery of
the fuse layer 67. The outer periphery of the fuse layer 67 and the
nickel wire 69 is integrally coated by an extruded heat bonding
layer 71, having the thickness of 0.2 mm, and made of polyethylene
(PE). This is the structure of the heating wire 61, of which outer
diameter as the finished product is 1.1 mm.
[0111] Accordingly, it is also possible to apply the present
invention to this "single-wire type" heating wire 61 as discussed
above, in the same manner as those of the first embodiment and the
second embodiment.
Fourth Embodiment
[0112] A fourth embodiment of the present invention will now be
described with reference to FIG. 9. FIG. 9 illustrates the
structure of a so-called "braid type" of heating wire 81, and it is
also possible to apply the present invention to this type of the
heating wire 81, likewise the case of the first through the third
embodiments.
[0113] The structure of the heating wire 81 according to the fourth
embodiment will now be made. There is a braided cord structure type
of resistive conductor 83. The resistive conductor 83 is made of a
plurality of thread bundles braided by a publicly known braiding
method, so as to form a continuous braid pattern extending in the
elongating direction. The thread bundles may be braided in a hollow
cylindrical shape, or braided on a core thread, and the core thread
shape will be preferable, because that shape will improve the
bending strength (flexibility) or the tensile strength, and because
that shape will be advantageous for the stable resistivity in order
to serve as the heater, and for the constant outer diameter of the
finished product.
[0114] The preferable material of the core thread may be glass
filament, polyester filament, aromatic polyamide filament, wholly
aromatic polyester filament, etc.
[0115] As for the plurality of the thread bundles, a metal wire
resistor material is used, at least partially, for the thread
bundles in any one direction (i.e. either in the right spiral
direction or the left spiral direction), and an insulating filament
material is used for the thread bundles in the other direction.
[0116] As for the metal wire resistor material, it is possible to
use a copper wire, a copper alloy wire, a nickel wire, a steel
wire, an aluminum wire, a nickel-chromium alloy wire, etc. This
wire may be used in a form of a single wire, or a stranded wires.
The wire may be used without any coating thereon, or with an
insulation coating material. Any material serving for insulating
electricity, already known as a prior art, may be used for the
insulation coating material. The necessity of the insulation
coating material will be determined on a case-by-case basis,
according to the using condition of a cord-type resistor body
obtained by the present invention.
[0117] As for the filament of the insulation material, it is
possible to use inorganic filament such as fiber glass, or
polyester filament such as polyethylene terephthalate, or organic
filament such as aliphatic polyamide filament, aromatic polyamide
filament, wholly aromatic polyester filament, etc. This kind of
material may be used in the form of mono-filament, multi-filament
or span. It is also possible to use a heat bonding filament having
a core-sheath combination structure, in which, any of these
filament materials, or an organic polymer material comprising any
of these filament materials, may serve as the core material, so
that the outer periphery of the core material may be coated by the
sheath material made of an organic polymer material having thermo
plasticity, such as polyolefin, polyester, polyvinyl chloride
resin, polyamide resin, etc. These materials may be selected on a
case-by-case basis, according to the balance of the strength of the
thread bundles in the right spiral direction and the left spiral
direction, and the using condition when used as of the heating wire
81.
[0118] The outer periphery of the resistive conductor 83 is coated
by an extruded heat bonding layer 85, having the thickness of 0.2
mm, and made of polyethylene (PE). This is the structure of the
heating wire 81, of which outer diameter as the finished product is
1.1 mm.
[0119] Accordingly, it is also possible to apply the present
invention to this "braid type" heating wire 81 as discussed above,
in the same manner as those of the first through the third
embodiments.
[0120] Although the heating wire 81 as illustrated in FIG. 9 has
the structure that the heat boding layer 85 is provided as the top
surface layer of the heating wire 81, it is also possible to
provide the heating wire 81 which only uses the resistive conductor
83, without using the heat bonding layer 85. In this case, the
insulation coating material of the metal wire resistor material as
discussed above, may serve as the heat bonding layer, or the heat
bonding filament used for the filament of the insulation coating
material, may serve as the heat bonding layer.
Fifth Embodiment
[0121] A fifth embodiment of the present invention will now be
described with reference to FIGS. 4, 5 and 10. According to the
first through the fourth embodiments, the all length of the heating
wire adheres to and is fixed on the base cloth. However, according
to the fifth embodiment, there is provided non-bonding portions,
which serves as detached parts.
[0122] Now referring to the seat heater 31 of FIG. 4, the parts
shown by letters A, A' will be bent and pulled in the direction of
the vehicle seat 41 as shown in FIG. 5, by relatively strong force,
while the seat heater 31 is incorporated in the seat 41. This is
because, these parts of the seat heater 31 are caught and pulled by
unillustrated threads in the direction of the inside of the vehicle
seat 41, so that the seat heater 31 is secured to the vehicle seat
41. At that time, to say nothing of the base cloth 11, the heating
wire 1 adhering thereto and being fixed thereon is also pulled in
the same direction. However, when such pulling force is applied to
the heating wire 1, the heating wire 1 might be considerably bent,
which would cause the heating wire being cut. This dangerous
situation will be further promoted by passengers sitting on and
removing from the vehicle seat 41.
[0123] Therefore, according to the fifth embodiment, these bending
parts are provided as the non-bonding portions, i.e. the parts at
which the heating wire 1 does not adhere to, and is not fixed on,
the base cloth 11. As illustrated in FIG. 10, there are hollow
parts 91, 93 formed at predetermined positions of the hot pressing
aid 15. When the application of the heat and pressure is done by
the pressing hot plate 27, the heating wire 1 will go inside the
hollow parts 91, 93, thereby the heating wire 1 at these points
will not adhere to and be fixed on the base cloth 11. Consequently,
the non-bonding portions may be provided at the predetermined
position of the heating wire 1.
[0124] The position of the non-bonding portion will be determined
on a case-by-case basis, and it is possible, not only to provide
the continuous form of non-bonding portions in the whole area of
the bending parts as discussed above, but also to provide the
intermittent non-bonding portions in these bending parts.
[0125] According to the fifth embodiment, the non-bonding portion
shall serve the detached part. However, it is also possible to
provide various structures of the detached part. For example, it is
possible to provide the non-bonding portions and the bonding
portions one after another, so that they may serve as the detached
part. Further, it is also possible to provide an adhering and fixed
part at which adherent strength is small, so that it may serve as
the detached part.
[0126] Further, when the depth of the hollow parts 91, 93 is
appropriately adjusted, the condition of the non-bonding portions
may be adjusted accordingly, so that the optimum condition of the
non-bonding portions may be provided. As for the adjusting means
for the hollow parts 91, 93, for example, it is possible to change
the depth of the hollow parts 91, 93 on a case-by-case basis, or it
is also possible to adjust the depth by intervening elastic
materials, etc., having an appropriate thickness, in the hollow
parts 91, 93.
Sixth Embodiment
[0127] A sixth embodiment of the present invention will now be
described with reference to FIGS. 5 and 11. According to the sixth
embodiment, in particular, the present invention is applied to the
vehicle seat 41 as illustrated in FIG. 5, in which, the vehicle
seat 41 being equipped with an air conditioning device. As
illustrated in FIG. 11, the vehicle seat 41 is equipped with an air
conditioning device 101. The air conditioning device comprises a
cold/hot wind supplier 103, a piping 105, and a plurality of
cold/hot air blowers 107, 109. The seat heater 31 (shown by an
imaginary line in FIG. 11) is inserted and placed in a space
between the surface cover 41 and the seat pad 45 of the vehicle
seat 41 having the above structure.
[0128] In the sixth embodiment, the seat heater 31 has the
structure that the heating wire 1 adheres to and is fixed on a
single sheet of the base cloth 11. Thus, the seat heater 31 has a
good ventilation performance, and there is no possibility that the
seat heater 31 would cause any bad effect to the cold/hot air
supply by the air conditioning device 101. In addition, by
appropriately selecting the heating function of the air
conditioning device 101 and the heating function of the 31, it is
also possible to provide more effective heating system of the
vehicle seat 41. For example, a passenger may first use the seat
heater 31 when starting the heating, and thereafter, the passenger
may switch to the heating by the air conditioner 101.
[0129] The present invention is not limited to the first through
sixth embodiments as described above.
[0130] For example, according to the first through the sixth
embodiments, although the clear polyethylene is used as the heat
bonding layer of the heating wire, it is also possible to use the
polyethylene in any color, by using any dyestuff, etc. In this
case, the bonding state (adherent state) between the heating wire
and the base cloth may be confirmed easily by the eyes. That is, as
for the seat heater in which the heating wire and the base cloth
have been melted and bonding to each other, when an inspector sees
the seat heater from the reverse side (the side on which the
heating wire is not placed), the inspector may see the transparent
color of the heat bonding layer of the heating wire. And on the
other hand, if there is any trouble in regard to the heat bonding
state between the heating wire and the base cloth, the inspector
cannot see the transparent color of the heat bonding layer of the
heating wire. This function is very useful from the viewpoint of
the quality control of the products.
* * * * *